It is known from DE-BM 1,932,642 to dispose, between the final damping roller of a damping unit and the first inking roller of the inking unit, either a single intermediate roller or, if the final damping roller is, for example, too far away from the first inking roller, two or more intermediate rollers in consecutive relationship and to engage the intermediate rollers with an inking or damping spreader roller.
The use of an intermediate roller pair is already known from a research report No. 3,216 "Damping Device" of the German Research Society for Printing and Reproduction Technology (FOGRA), at page 30, FIG. 38. Here, both damping liquid and ink are applied to the plate cylinder by way of the applicator rollers of the damping unit. This kind of operation is satisfactory for many printing jobs, for example, in the case of thickly coated subjects which do not tend to mottle.
It is also known from DE 3,637,460 to engage a first rider roller and, as an over-rider or tandem roller, a second rider roller with a common applicator roller of a damping unit in order to reduce, by rolling of the rider roller on the applicator roller, the excess of damping agent which is due to the blank part of the plate cylinder and which may of course leave unwanted streaks on the end product.